

;;              dr_so4_monolayers_pcage = n_so4_monolayers_pcage * 4.76e-10

;; thickness of the so4 monolayers (m)
;; for so4(+nh4), use bi-sulfate mw and 1.77 g/cm3,
;;    --> 1 mol so4(+nh4)  = 65 cm^3 --> 1 molecule = (4.76e-10 m)^3
;; aging criterion is approximate so do not try to distinguish
;;    sulfuric acid, bisulfate, ammonium sulfate


   ;; http://en.wikipedia.org/wiki/Calcium_nitrate 

   mw = 164.088 ;; Ca(NO3)2  
   rou = 2.504  ;; g/cm3 

   vv = mw / rou ;; cm3 
   vv = vv / 6.022e23

   rm = vv^(1./3.) * 1.e-2 ;; m 

   print("rm : "+rm) 


